How does glass tempering furnace operate?

Glass tempering furnace uses physical or chemical methods to form a compressive stress layer on the glass surface and a tensile stress layer inside;

When the glass is subjected to external force, the compressive stress layer can offset part of the tensile stress and avoid the glass from breaking, thus achieving the purpose of improving the strength of the glass.

Moreover, the microcracks on the glass surface become finer under this compressive stress, which also improves the strength of glass to some extent.

At present, the common physical tempering method is to heat the glass to its softening point (about 650℃). At this time, the glass can still keep its original shape, but the particles in the glass have certain migration ability, so that the internal stress can be quickly eliminated, and then the tempered glass in glass tempering furnace is quenched by blowing. When the temperature is balanced, the glass surface produces compressive stress and the inner layer produces tensile stress, that is, the glass produces uniform and regularly distributed internal stress, which improves the glass performance.

At the same time, due to the uniform stress in the glass, once the glass is broken by the impact exceeding its strength, it will explode into small particles under the action of internal stress, which improves its safety. Therefore, tempered glass can also be called prestressed glass or safety glass.

During the tempering process in glass tempering furnace, wind spots and stress spots generally appear. Wind spots are formed due to uneven cooling during the cooling process. From a special point of view, light and dark stripes will appear on the glass surface.

Stress spots are also caused by uneven stress. For example, during the heating process, there is a temperature difference between the edge and the middle of the furnace, which leads to uneven stress.

. At present, there is no way to completely avoid stress spots, but well-designed tempering equipment can minimize the visibility of stress spots.